Gunstock of two sections pivotal relative to each other



June 18, 1968 Filed J. w. KIMBALL 3,388,494

' GUNSTOCK OF TWO SECTIONS PIVOTAL RELATIVE TO EACH OTHER 2 Sheets-Sheet l Maren 25, 1966 E m E 9 ll. '2 v a Q K: g 2

l M Q w INVENTOR.

\o JOHN W. AIMBAlL fi MC4L @Lo-mfi;

A TTORNEYS June 18, 1968 J. w. KiMBALL GUNSTOCK OF TWO SECTIONS PIVOTAL RELATIVE TO EACH OTHER 2 Sheets-Sheet 2 Filed March 25, 1966 INVENTOR. Jo/M/ W. K/MB/ML ATTORNEYS United States Patent 3,388,494 GUNSTOCK OF TWO SECTIONS PIVOTAL RELATIVE TO EACH OTHER John W. Kimball, 1216 Garden Road, Milford, Mich. 48042 Filed Mar. 25, 1966, Ser. No. 537,353 19 Claims. (Cl. 42-74) ABSTRACT OF THE DISCLOSURE This invention relates to improvements in a gunstock construction and more particularly to a device which substantially reduces both the recoil and the tendency of the gun to move upward or jerk when it is fired. The stock is formed with two sections having a flexible strap interposed between the sections adjacent to the top of the stock and a spring between the sections below the strap so that the two sections can rotate in a segment of an are relative to each other and to the top of the stock. This structure creates a moment arm or couple which opposes the tendency of the gun to move upward when it is fired.

This invention relates to improvements in a gun construction and more particularly to the improvement in a gunstock which permits better control of the gun by the operator.

It is commonly known that the recoil :of a gun causes the barrel to shift in a generally upward direction and to the left. In an automatic gun which is firing rapidly, this becomes a force which is practically uncontrollable so that effective use of the weapon is not always possible after the first few shots when rapid firing is being used.

It is an object of the present invention to provide an improved gunstock which not only reduces to a very minimum the change of position of the muzzle of the gun in continued firing but also relieves the shock against the shoulder of the gunner making it possible for him to maintain a stable position with a well-aimed firearm under rapid firing conditions.

Another object of the invention is a control device for a gunstock which is readily adjustable depending on the ammunition used and the needs of a particular operator.

It is a further object of the invention to provide a fully-automatic, shoulder-fired weapon which converts recoil energy into a beneficial effect which results in dropping the barrel and bringing it back into the previously mounted position. Thus, the general tendency of the barrel to rise after each shot is eliminated; and, as a secondary advantage, there is dampening of the recoil in the absorption of the energy to accomplish the beneficial result causing less disturbance of the gunner and the gun attitude.

Other objects and features of the invention relating to details of construction and operation will be apparent in the following description and claims.

Drawings accompany the disclosure and the various views thereof may be briefly described as:

FIGURE 1, a side elevation of a gun showing the improved stock.

FIGURE 2, an end view of the gun stock.

FIGURE 3, an axial section of the gun stock showing the inner design construction taken on line 33 of FIG- URE 2.

FIGURE 4, a sectional view of the gun stock taken on line 44 of FIGURE 3.

FIGURE 5, a view of an adjusting plug.

FIGURE 6, a view of an adjusting device utilized for control of tension.

Referring to the drawings:

ICC

In FIGURE 1, there is shown the outline of a standard government rifle sometimes referred to as 21 M14 rifle having a barrel 1!), a magazine 12, a trigger 14 and a stock composed of a neck portion 16 and a butt portion 18.

The details of operation of the gun are not essential to the description of the particular invention; but, in general, the gun shown is a rapid firing, relatively high-powered, manual arm. In the design shown, the stock of the gun is preferably a molded plastic although it can be formed of solid wood. In the design shown, the stock has a metal skeleton construction formed of a member having two side walls 20 with perforated portions 22 and 24 at the top and bottom of the neck portion 16 of the stock so that plastic can be mounted around the skeletal member to give a solid unitary construction.

The skeleton member has a hardened steel leaf portion 26 which carries upwardly and rearwardly from the neck portion 16 of the stock to the butt portion 18 of the stock, the rear part of the skeleton means being perforated in the portion marked generally at 28 to interlock with the plastic stock which is formed with a relatively large hollow cavity 30. This cavity terminates in a forward wall 32 which is spaced from the butt portion of the stock which terminates at a rearward wall 34 leaving a relatively wide opening 36 between the neck portion and the butt portion connected by an integral resilient hinge portion 40 reinforced by the metal skeletal part 26. Hinge portion 40 serves as a pivot joint, and this part can be suitably heat treated and tempered to have a resilient characteristic, thereby forming a resilient bendable strap hinge portion betvi {een the neck portion 16 and the butt portion 13 of the stoc The opening 36 extends transversely of the stock completely across it and this is closed at the sides by a U-shaped shield portion shown generally at 42 having two side legs 44 which extend upwardly and are anchored at the sides by screws 46. The forward edges of the legs 44 are slidable in slots 48 formed in the rearwardly extending lips 50 of the rear portion of the neck of the stock, there being a relatively tight slip fit between the parts.

A cross pin .52 firmly mounted between the legs 44 operates in a cross slot 54 of the rear portion of the neck of the stock to limit the motion between the neck and the butt permitted by the hinge or resilient connection 40. In the rear wall 32 which is a relatively thick wall is mounted a threaded plug 60 shown in detail in FIGURE 5, this plug having a reduced portion 62 at the rear end thereof provided with slots 64 for engagement with inwardly extending lugs 66 of an adjustment tube wrench or screwdriver 68 which can be actuated by a narrowed lug 70 which projects outwardly from the shoulder plate 72 at the rear portion of the stock butt. Tube 68 telescopes with reduced portion 62 of plug 60 and the plug serves as an adjusting screw.

Screws 74- hold the shoulder plate in position, and the lug 76 has a cylindrical fore-part 76 which is secured to the rear end of the tube wrench 63. The forward end of the plug 69 has a spring fit recess for a compression spring 78 which also seats in an opposed recess in the rearward surface 34 of the neck portion of the stock. Thus, it will be seen that the spring 78 can be controlled in its compression by manipulation of the lug 70= actuating the tube wrench or screwdriver 68 and the lugs 66 can move in the slots 64 to permit this adjustment.

In FIGURE 2, it will be seen that the stock portion 18 is angled from the general vertical plane of the gun in a manner which is common to permit the shoulder plate to be suitably adjusted to the gunners shoulder. If desired, the angle of this relationship of the stock can be adjusted but no mechanism is shown for this adjustment in the present disclosure.

It will be noted that the hinge point 41, as shown best in FIGURE 1, is above the center line of the bore so that the energy developed in the automatic, high-powered weapon on which this invention is best used causes a closing of the opening 36 against the action of the spring 78 and the spring force in the hinge area 40. After each shot, the return force of the spring 78 and the spring 40 moves the muzzle of the gun upwardly again to re-align it with the target before the next shot. This effect can be readily observed in the firing of a weapon with this type of stock. It is not necessary to adjust the spring 78 to any particular range; but if it is set, for example, for .200 yards, it will be effective for any target closer than that. For long range work, it can be adjusted differently. It is essential, of course, that the gun be securely held against the shoulder as is usual to provide a reaction force to permit the hinge action of the stock; but, actually, with this attitude, the gunner is subjected to less recoil shock because the recoil is transferred into work against the springs above described and there is much less tendency s to throw the gunner and the gun out of the original attitude.

With the structure shown, utilizing a reasonably heavy spring 78 in the nature of to pounds compression, and utilizing also the resilence of the connection generally shown at 40, it has been found that the recoil of the gun actually brings the barrel down each time so that as it recovers from the recoil, it is again in the position previously aimed before firing. Thus, the gun is easily maintained in the aimed position. It does not tend to climb away from the targets as in previous constructions. As above explained, it has also been found that the recoil against the shoulder of the gunner is much less so that he is not moved from an original stable position under conditions of continuous firing of the automatic weapon. Both of these factors contribute to the stability of the gun and thus to a much more accurate and less wasteful use of the gun.

I claim:

1. In a fully-automatic gun of the type having a support such as a stock and a barrel mounted thereon, that improvement in the support which comprises:

(a) a two-section support in which the sections are associated for relative motion about an axis transverse to the line of fire and adjacent the top of the support, said sections being spaced to permit closing of a gap below said axis in response to recoil force of said gun,

(b) a barrel mounted on said support having a recoil force line below said axis, and

(c) means to resiliently resist said closing action whereby recoil energy moves the gun barrel down after each shot and reaction of said means moves the gun barrel up to the original attitude.

2. In a gun of the type having a support such as a stock and a barrel mounted thereon, that improvement in the support which comprises:

(a) a two-section support in which a neck section and a butt section are associated for movement relative to each other about an axis transverse to the line of fire and adjacent the top of the support with the sections being spaced to permit closing of a gap below said axis in response to recoil force of said gun,

(b) a barrel mounted on said neck section having a recoil force line below said transverse axis with reference to the normal horizontal shooting position of said gun, and

(c) means associated with said sections to resiliently resist said closing action,

whereby recoil energy moves the gun barrel downward after each shot and reaction of said means moves the gun barrel upward toward the original attitude.

3. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improved support 4- v as defined in claim 2 in which at least a part of said stock section is angled from the vertical plane of said gun.

4. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 3 in which said neck and butt sections are associated for relative motion about said transverse axis by a resilient bendable strap.

5. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 4 in which said resilient means is positioned below said transverse axis.

6. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 5 in which said resilient means comprises at least in part one compression spring.

7. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 6 having an adjusting device associated with said resilient means for adjusting the degree of resistance of said resilient means to said closing action.

8. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 7 in which said adjusting device comprises a screw member threadedly connected to said butt section and abutting said spring, and screw driving means operatively connected to said screw member and having a part thereof at the rear of said butt portion available for adjustment.

9. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 8 in which said screw driving means has a telescoping connection to said screw member.

10. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 2 in which said neck and butt sections are associated for relative motion about said transverse axis by a resilient bendable strap.

11. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 10 in which said resilient means is positioned below said transverse axis.

12. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 11 in which said resilient means comprises at least in part at least on compression spring.

13. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 12 having an adjusting device associated with said resilient means for adjusting the degree of resistance of said resilient means to said closing action.

14. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 13 in which said adjusting device comprises a screw member threadedly connected to said butt section and abutting said spring, and screw driving means operatively connected to said screw member and having a part thereof at the rear of said butt portion available for adjustment.

15. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 14 in which said screw driving means has a telescoping connection to said screw member.

16. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 2 having an adjusting device associated with said resilient means for adjusting the degree of resistance of said resilient means to said closing action.

.17. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in 5 the support as defined in claim 3 having an adjusting device associated with said resilient means for adjusting the degree of resistance of said resilient means to said closing action.

18. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 4 having an adjusting device associated with said resilient means for adjusting the degree of resistance of said resilient means to said closing action.

19. In a gun of the type having a support such as a stock and a barrel mounted thereon, the improvement in the support as defined in claim 10 having an adjusting device associated with said resilient means for adjusting the degree of resistance of said resilient means to said closing action.

References Cited UNITED STATES PATENTS 724,273 3/ 1903 Ermel 4274 1,334,467 3/1920 Moller 4274 1,468,354- 9/ 1923 Caretto 4274 2,400,422 5/ 1946 Johnson 4271 2,453,394 11/ 1948 \Vittman 4273 2,970,398 2/ 1961 Crouch 4272 X BENJAMIN A. BORCHELT, Primary Examiner. 

